The welding of large flanges is a component that connects pipes to each other, connected to the pipe end, and sealed with a gasket between them. Welding of large flanges, also known as welding flanges, has holes on the welding flange
Tight connection is a type of disc-shaped component commonly found in pipeline engineering.
High forging speed (150-200mm/s) is required for metal welding with good thermal conductivity of large flanges. Regarding the same metal, there is a large temperature gradient in the interface area due to the cold nature of the joint
Need to increase forging speed. The forging pressure Fu Fu is usually indicated by the pressure per unit area, that is, the forging pressure strength. The size of the forging pressure should ensure that the liquid metal inside the interface can be extruded
Undergoes certain plastic deformation.
Due to its outstanding inductive function, large flanges are widely used in chemical, construction, water supply, drainage, petroleum, light and heavy industries, refrigeration, sanitation, plumbing, power, and manufacturing industries
Cheng.
When welding large flanges, if the top forging pressure is too small, the deformation is insufficient and the joint strength decreases; If the top forging pressure is too strong, the deformation will be too large, and the crystal grain will be twisted and severe, which will also reduce the impact toughness of the joint
The speed of bright light will cause an increase in temperature gradient, so when welding metals with good thermal conductivity (copper, aluminum alloys), special steel flanges require a large forging pressure (150-400Mpa).
In addition to the above process parameters, the preheating temperature and preheating time should also be considered for the preheating bright spot welding parameters. The preheating temperature is selected based on the workpiece cross-section and material function. When welding low-carbon steel,
700-900 degrees.
Generally, manual arc welding is used for welding large flanges, with irregular arc welding lines and easy burning and undercutting of the lining edge, which cannot be eliminated even by machining, resulting in poor appearance quality; 2. Because it is usually a different type of steel
Large welding current, poor control of welding current, and easy occurrence of undercutting or incomplete welding. For large convex flanges, the welding seam needs to be processed, so that there is less deposited metal between the lining ring and the flange
Post time: Apr-08-2024